ETL Listed
with a special “Suitable for Damp
Locations” rating. Find that statement on those cheapo "duct fan on
a plate" knock-offs.

Mounting plates are 18 ga. G90 galvanized steel on the V1D and
V2D, 20ga. G90 on the V1

.
G90 is the thickest coating of galvanization that is available and what most
highway street signs are made out of.

Call or e-mail us with your crawlspace
measurements... 800 685 8263 /
volkosupply@yahoo.com
We will help calculate the number of fans necessary, offer fan options and
provide installation tips.

The Tjernlund UnderAire™ Series Crawl Space
Ventilators are designed to circulate fresh outdoor air underneath homes
and porches. Excessive humidity levels in Crawl Spaces is the leading
cause of premature rotting of support columns, joists, floors and beam
supports. Humidity can promote fungus growth and increased termite
activity.

Humidity may also cause plumbing failures due to rust
and corrosion. Constant operation helps vent radon gases, treated wood
off-gasing and other odors that might migrate into living areas.

All Ventilator models are equipped with a factory
installed and pre-wired thermostat which will prevent operation of the
fan below 35°F. Deluxe models (V1D & V2D) are controlled by a
de-humidistat which actuates the fan if the relative humidity rises above
the selected set-point.

Screws and masonry wall anchors are included.

MOUNTING LOCATION

Mount Crawl Space Ventilator inside the crawl space behind
existing foundation ventilation openings. Ventilation openings shall be within
three feet of each corner of the building.

NOTE: Crawl Space Ventilator must be mounted with the electrical
control box and the motor facing the interior of the crawl space.

1. Remove existing doors or covers on ventilation openings
around the perimeter of the building.

2. Position the Crawl Space Ventilator over the ventilation
opening.

3. If installing on foundation block or brick, mark location in
the four corners of the metal face plate and drill 5/16" holes with masonry bit.
Install wall anchors into openings and secure Crawl Space Ventilator to the wall
with four screws.

If installing on a wood header, rim joist or mesh on existing
crawl space vent, secure Crawl Space Ventilator with screws, washers and nuts in
the four corners of the Ventilator metal face plate.

SPECIFICATIONS

How to determine the number of
UnderAire™ Ventilators needed:

Calculate the cubic area of the crawl space by multiplying the
length x width x height. Divide this number by 15 to determine the minimum CFM
necessary to fully ventilate the space in 15 minutes.

Example: 20' wide x 40'
long x 3' high crawl space = 2,400 cubic ft.

2400 cubic ft. ÷ 15 minutes = 160 CFM of ventilation.

Choose two V1 or V1D ventilators or one V2D ventilator.

Ballpark
Pricing

Ballpark pricing is based on
3 options of fan(s) with control for the example above...
If a crawlspace requires 160 CFM's you could use...